During the wet milling of corn, fouling of the equipment by protein-containing fluids can occur. The wet milling processing of shelled corn is employed to obtain staple products such as corn oil, dextrose, corn syrup, high fructose corn syrup, dextrins, dry starches and feeds. The principle steps in the wet milling of corn include steeping, milling, recovering and processing. During the steeping process, corn kernels are softened by soaking in a hot, dilute solution of sulfurous acid (i.e., water/sulfur dioxide). The softened kernels are then passed through grinding mills and separators where the germ is removed and the starch and gluten are separated from the coatset hull and fibers. The starch is then separated from the gluten which is added to the fibrous material and processed into a high protein animal feed. The starch is recovered as dry starch or further processed into dextrose and fructose. The sulfurous acid steepwater initially used to soften the corn contains solubles which are recovered for use in feeds. The steepwater solids are recovered by evaporation and drying. The solids recovered from evaporating and drying the steepwater are used as additives to livestock feeds to enhance their nutritional value.
The deposition of organic, proteinaceous materials in the steepwater evaporators limits throughput and is a bottle-neck in the wet milling corn process. To cope with such organic deposition fouling, such evaporators are typically boiled out with an acid and/or caustic solution. Such boil-out procedures result in undesirable downtime for the equipment. The present invention is directed to a process for controlling deposition in such evaporators so as to minimize the requirement for such boil-out procedures.